Biamonti 223 – Allegro in B-flat major, 1798–1800. (Sketch). Cited by Nottebohm as the beginning of a sketch originally intended for the final movement of the Quartet Opus 18 No. 6, in which, as in the final version of the work, the Malinconia theme was to be introduced. (Nottebohm, II, pages 106–164).

This sketch is held at the Staatsbibliothek zu Berlin – Preußischer Kulturbesitz, in the sketchbook labelled Autograph 19e, on folio 12v (8v in the newly rearranged foliation). This sketchbook was analysed and transcribed by Richard Kramer in his volume A Sketchbook from the Summer of 1800, published in 1996 by the Beethoven-Haus in Bonn.

Biamonti 223 – Allegro in B-flat major, 1798–1800. (Sketch). Cited by Nottebohm as the beginning of a sketch originally intended for the final movement of the Quartet Opus 18 No. 6, in which, as in the final version of the work, the Malinconia theme was to be introduced.

Nottebohm wrote:
“Auf mehreren Bogen und Blättern, die theils zusammengehören, theils nicht, finden sich Arbeiten zu den genannten Quartettsätzen und zu andern Compositionen (Die Manuscripte waren früher bei G. Petter in Wien). Wir verzeichnen hier […] den Anfang einer Skizze zu einem Allegro das ursprünglich zum letzten Satz des Quartetts in B-dur bestimmt war und in dem, ähnlich wie im gedruckten Stück, das Thema der Malinconia angebracht werden sollte, das jetzige Thema des genannten Satzes in einer früheren und in einer späteren Fassung.”

The sketchbook Autograph 19e is in fact a collection of three distinct and separate gatherings. The Allegro in question forms part of the first gathering (folios 1–11), which is almost entirely devoted to the String Quartet Op. 18 No. 6.